The present invention pertains to a bracket for attachment to a movable window and connection to an automotive window lifting mechanism.
In vehicles, and especially automobiles, it is highly desirable to have movable windows. With reference to automobiles, windows are displaceable upwardly and downwardly relative to a door assembly by use of a manual crank or an electrically driven window lifting mechanism. Many window lifting mechanisms include a scissoring linkage which transfers motion from a manual crank or electric drive to a window connected to the window lifting mechanism. The scissoring linkage is used in order to limit the movement of the window in a generally vertical direction. A cross member is attached to the scissoring linkage to provide a support for the movable window.
Mounting brackets or window lift brackets are often used to attach the movable window to the cross member attached to the scissoring linkage. These brackets generally are attached to a mounting edge of the window at two spaced apart locations and a portion of the bracket is attached to the window lifting cross member.
Prior art brackets presented many problems in a movable window assembly, are difficult to manufacture, and are relatively expensive. With regard to the problems associated with prior art window lift brackets, these brackets are typically manufactured from a stamped strip of metal which has been deformed to a specified bracket configuration. These deformed metal components are subject to damage and failure as the result of corrosion thereby providing a weak link in the movable window assembly.
With regard to the manufacturability of such prior art window lift brackets, many opportunities for complications and defect arise. We will briefly review the numerous steps involved in producing a window lift bracket as found in the prior art in order to appreciate and elaborate on the aforementioned problems. Initially, a strip of metal is stamped or cut to a desired size. Next, the metal component is stamped, bored or drilled to provide through holes which will be used as described here and below. The stamped metal component is deformed to form a bracket having a generally "Y" shaped cross section. The deformed metal component must now be protected by painting, anodizing or other means to delay the corrosion process. Once protected, plastic mounted clips are positioned in a channel portion of the bracket and secured in the thru holes by use of a heat staking process. The base of the bracket is drilled for receiving a fastener which will be used to attach the bracket to the lift mechanism cross member.
In applying the prior art lift bracket to window, an adhesive is disposed in the channel portion of the lift bracket and the lift bracket is attached to the mounted edge of a movable window. The window, with two or more brackets positioned thereon, is subjected to a heat curing process in order to cure the adhesive. A heat curing adhesive is used in order to properly adhere the adhesive to the surfaces of the bracket and window.
As may be understood from the description hereinabove, there are numerous opportunities for problems to arise in the manufacture of a window lift bracket as set forth by the prior art. For example, if the bracket is not properly formed it may not properly fit on the window or function in the movable window assembly. In each step of the fabrication process a new operation, coating, or joining method is used, each presenting its own opportunity for problems.
For example, as mentioned, clips must be used with the deformed metal bracket in order to prevent the bracket from scratching the window glass and the protective coating on the window. The plastic clips are an individual piece part which must be designed, purchased, and managed in the manufacturing system. The clips are typically produced by selectively cutting an extruded plastic strip. Each clip must be cut to a generally precise dimension thereby requiring an additional inspection step. The clips must also be heat staked to the metal bracket. The heat staking process deforms a portion of the plastic clip over an abutting portion of the metal bracket. If the plastic portion is not properly melted, it may not be securely held to the metal bracket which could result in a release of the window from the bracket under certain circumstances. Clearly, it is not desirable to have a release of the window from the bracket.
Additionally, an adhesive is disposed in a channel portion of the metal bracket to secure the window to the bracket. The adhesive must be selected to attach or adhere to the plastic clip, the metal bracket (or the protective surface of the metal bracket) and the window glass and/or coating. The numerous and diverse material properties involved can make selection of an appropriate adhesive somewhat difficult. Further, if the metal bracket begins to corrode, the corrosion could result in the adhesive detaching from the metal bracket.
As may be clear, there are numerous problems associated with the manufacture and use of metal window lift brackets as currently used in the prior art. As such, it is important to find a window lift bracket which will overcome the problems associated with the prior art devices.